1. Field of the Invention
This invention pertains to a new tertiary amine compound and its method of preparation. More specifically, energetic liquid fuels have been invented for liquid bipropellant systems wherein the fuels are azido derivatives of tertiary amines.
2. Description of the Prior Art
Current storable liquid bipropellant systems are based on using storable liquid oxidizers such as nitrogen tetroxide (NTO), 75NTO/25NO(MON) (75% nitrogen tetroxide/25% nitric oxide), and inhibited red fuming nitric acid (IRFNA) and storable liquid fuels such as hydrazine derivatives and hydrocarbons. The liquid rocket fuels should have the following desired properties: (1) high energy and density, (2) wide liquid range, (3) minimum hydrogen content, and (4) hypergolic with NTO, MON, or IRFNA. Hydrazine derivatives have higher energy than hydrocarbons and are the preferred liquid rocket fuels. In particular, monomethylhydrazine (MMH) is the current fuel of choice because of its low freezing point. However, higher energy fuels are required.
Besides the requirement for higher energy, increasing importance is being placed on the development of minimum smoke liquid bipropellants. Minimum smoke propellants produce virtually no primary smoke and little or no strong nucleation for secondary smoke, but continue to produce water vapor as a combustion product. Hydrogen containing oxidizers and fuels produce water vapor in the exhaust plume, directly and by secondary combustion with atmospheric oxygen. Under some "con-trail" conditions, this water vapor will condense and produce a fog even in the absence of a potent nucleator-like hydrogen chloride. A much wider range of "smoke-free" conditions and a slower formation of this secondary smoke/fog are typical, however, as compared to the behavior of plumes containing large quantities of hydrogen chloride or other strong nucleators. The following criteria can be established for defining the types of oxidizers and fuels that would be most desirable for achieving a minimum smoke liquid bipropellant system:
1. Use no metal ingredients--the major contributors to primary smoke. PA1 2. Eliminate halogen containing incredients so that no HCl or HF would be formed as combustion products. PA1 3. Reduce hydrogen content--to minimize formation of water. PA1 4. Maximize formation of CO, CO.sub.2, and N.sub.2 as the major combustion products.
In evaluating candidate liquid bipropellant systems that would have minimum smoke, two critical parameters were selected as the criteria. One was the specific impulse density (I.sub.d), and the other was the formation of secondary smoke caused by the condensation of water vapor. Both the mole percent of H.sub.2 and H.sub.2 O in the combustion products is important since hydrogen will react with ambient oxygen to form water.